I think you've actually buried a much broader commentary on tolerances and complexity and interoperability in here, too.
The mechanical-averaging voltage regulator worked for the design because it only had to work in the context of the specific model of car it was going into. It didn't have to produce 5v for any application that needs 5v; it just had to produce "5v" for the instruments in the '72 Dodge Challenger. That makes it a pretty terrible 5v regulator, but a pretty great part for the system it was designed to fit into if the mechanical-averaging version is more reliable or cheaper or more robust than the fancy electronic versions.
But if I'm designing a 5v regulator to be sold as a 5v regulator, well... I don't know what system its getting installed into so I won't have much luck selling one that, over a long enough time span, averages out to supplying 5v of power when its supplying power. So I have to design in tight tolerances, and everyone integrating my regulator has to design for tight tolerances, etc.
The good news is that now anyone can buy my regulator and get a reliable 5v - interchangeable parts! But the bad news is now every system on both sides has additional complexity for the sake of complying with our standard.
We see this _all the time_ in software, especially comparing old software to new. Why is Roller Coaster Tycoon so much more elegant and efficient than a modern game written on Unity? Sure, good tastes probably factor in - but that taste from the author was allowed to shine because it was designed as a complete system, not a bunch of component subsystems from different teams and vendors stitched together.
You make a great point. With the Dodge regulator, I seriously doubt it was just for the Dodge Challenger. It was probably used across the entire Chrysler line, for years. Enough cars were built to totally justify its design. I don't know when semiconductor voltage regulators appeared in a single package.
In 1972, the electro-mechanical regulator was also likely far cheaper than a solid state one. The car didn't have a single transistor in it outside of the (rather expensive) radio. (There was an upgrade available for the ignition to make it "electronic" - it had one transistor!) The alternator of course had diodes in it.
The rough 5V also enabled the instruments to be made cheaper.
The mechanical-averaging voltage regulator worked for the design because it only had to work in the context of the specific model of car it was going into. It didn't have to produce 5v for any application that needs 5v; it just had to produce "5v" for the instruments in the '72 Dodge Challenger. That makes it a pretty terrible 5v regulator, but a pretty great part for the system it was designed to fit into if the mechanical-averaging version is more reliable or cheaper or more robust than the fancy electronic versions.
But if I'm designing a 5v regulator to be sold as a 5v regulator, well... I don't know what system its getting installed into so I won't have much luck selling one that, over a long enough time span, averages out to supplying 5v of power when its supplying power. So I have to design in tight tolerances, and everyone integrating my regulator has to design for tight tolerances, etc.
The good news is that now anyone can buy my regulator and get a reliable 5v - interchangeable parts! But the bad news is now every system on both sides has additional complexity for the sake of complying with our standard.
We see this _all the time_ in software, especially comparing old software to new. Why is Roller Coaster Tycoon so much more elegant and efficient than a modern game written on Unity? Sure, good tastes probably factor in - but that taste from the author was allowed to shine because it was designed as a complete system, not a bunch of component subsystems from different teams and vendors stitched together.